Signal control unit for an organic light emitting diode display device, method of manufacturing the same, and organic light emitting diode display device including the same

ABSTRACT

A signal control unit for an organic light emitting diode (OLED) display device, includes a substrate structure including a plurality of active elements each corresponding to a pixel, a lower metal pattern disposed on the substrate structure, and electrically connected to a portion of the plurality of active elements, an insulating interlayer disposed on the substrate structure and at least partially covering the lower metal pattern, a via contact penetrating through the insulating interlayer and connected to the lower metal pattern, a metal electrode disposed on the insulating interlayer, and connected to the via contact, and an electrode passivation layer pattern substantially covering the metal electrode to expose a center portion of an upper surface of the metal electrode while covering a remainder of the upper surface and a side surface of the metal electrode. Therefore, leakage current which flows through the side surface of the metal electrode is suppressed.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No.10-2018-0044552, filed on Apr. 17, 2019 and all the benefits accruingtherefrom under 35 U.S.C. § 119, the contents of which are incorporatedby reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a signal control unit for an organiclight emitting diode (OLED) display device, a method of manufacturingthe same, and an OLED display device including the same. Moreparticularly, the present disclosure relates to a signal control unitfor an OLED display device capable of controlling signals for displayingimages using a light emitting phenomenon of organic material, a methodof manufacturing the signal control unit for an OLED display device andan OLED display device including the signal control unit.

BACKGROUND

Generally, an OLED display device may include a signal control unit forcontrolling a signal for each pixel, a light emitting unit forgenerating light using an organic material in response to the signal,and a protection unit formed on the light emitting unit to protect theunit as a whole.

The signal control unit may include a substrate structure, lower metalpatterns electrically connected to a portion of active elements includedin the substrate structure, an insulating interlayer covering thesubstrate structure and the lower metal patterns, via contactspenetrating from the insulating interlayer to be electrically connectedto the lower metal patterns, metal electrodes disposed on the insulatinginterlayer to be electrically connected to the via contacts, and anelectrode passivation layer pattern disposed between the metalelectrodes to protect side portions of the metal electrodes.

In detail, after forming an electrode passivaiton layer on the metalelectrodes and the insulating interlayer, a planarization process isperforming against the electrode passivation layer to expose uppersurfaces of the metal electrodes. Therefore, the electrode passivationlayer pattern is formed.

However, the upper surfaces of the metal electrodes may be damaged whilecarrying out the planarization process. Therefore, opticalcharacteristics of the OLED display device may be degraded. In addition,dishing phenomena may occur in the electrode passivation layer patterndue to the planarization process. Further, the side portions of themetal electrodes may be exposed due to the dishing phenomena. Therefore,current leak may occur through the side portions of the metalelectrodes.

On the other hand, dishing phenomena may occur to the via contacts whileperforming the planarization process after the via contacts are formed.A step portion may be undesirably formed to the metal electrodes due todishing phenomena which occurs to the via contacts. In particular, sincethe via contacts are located at each central portion of the metalelectrodes, the step portion may occur to the central portion of each ofthe metal electrodes. Therefore, the reflectivity of the metalelectrodes reflecting the light generated in the light emitting unit maybe reduced, so that the optical characteristics of the OLED displaydevice may be further reduced.

SUMMARY

The example embodiments described herein provide a signal control unitfor an OLED display device capable of suppressing damage to the metalelectrodes present in conventional device, as well as a loss ofreflectivity and a leakage current which flows along a side portion ofthe metal electrodes as described in the Background.

The example embodiments of the present invention provide a method ofmanufacturing the signal control unit for an OLED display device.

The example embodiments of the present invention provide an OLED displaydevice including the signal control unit capable of suppressing a damageof metal electrodes, a loss of reflectivity and a leakage current whichflows along a side portion f the metal electrodes.

According to an example embodiment of the present invention, a signalcontrol unit for an OLED display device, includes a substrate structureincluding a plurality of active elements for pixels, a lower metalpattern disposed on the substrate structure, and being configured to beelectrically connected to a portion of at least one of the activeelements, an insulating interlayer disposed on the substrate structureto cover the lower metal pattern, a via contacts penetrating through theinsulating interlayer to be connected to the lower metal pattern,respectively, a metal electrode disposed on the insulating interlayer,and being configured to be connected to the via contact, and anelectrode passivation layer pattern covering a peripheral portion of anupper surface and the side surface of the metal electrode to expose acenter portion of the upper surface of the metal electrode such thatleakage current which flows through the side surface of the metalelectrode is suppressed.

In an example embodiment, the electrode passivation layer patternincludes a first passivation film pattern covering the peripheralportions of the upper surfaces and the side surfaces of the metalelectrodes, and a second passivation film pattern disposed on the firstpassivation film pattern.

In an example embodiment, the via contact may be connected to aperipheral portion of a lower surface of the metal electrode such thatthe metal electrode includes a step portion at the peripheral portionthereof due to dishing phenomena caused by the via contacts.

Here, the electrode passivation layer pattern may cover the step portionto suppress the peripheral portion of the metal electrodes from beingexposed.

According to an example embodiment of the present invention, a method ofmaking a signal control unit for an OLED display device includespreparing a substrate structure including a plurality of active elementsfor pixels, forming a lower metal pattern on the substrate structure,the lower metal pattern being adapted to be electrically connected to atleast one of the active elements, forming an insulating interlayer onthe substrate structure to cover the lower metal pattern, forming a viacontact penetrating through the insulating interlayer, the via contactbeing connected to the lower metal pattern, and forming a metalelectrode on the insulating interlayer to be connected to the viacontact, forming an electrode passivation layer pattern covering aperipheral portion of an upper surface and a side surface of the metalelectrodes to expose a center portion of the upper surface of the metalelectrode such that leakage current which flows through the side surfaceof the metal electrodes is suppressed.

In an example embodiment, the via contact may be connected to aperipheral portion of a lower surface of the metal electrode such thatthe metal electrode includes a step portion at the peripheral portionsthereof, which may occur due to dishing phenomena caused by the viacontacts.

Here, the electrode passivation layer pattern may be formed to cover thestep portion to suppress the peripheral portions of the metal electrodesfrom being exposed.

In an example embodiment, forming the electrode passivation layerpattern may include forming an electrode passivation layer along aprofile defined by the insulating interlayer and the metal electrode,and performing a dry etch process against the electrode passivaitonlayer using an etch selectivity between the electrode passivation layerand the metal electrode to pattern the electrode passivation layer.

Here, the electrode passivation layer may be formed using a material ofone of oxide or nitride.

In an example embodiment, forming the electrode passivation layerpattern may include forming a first electrode passivation film along aprofile defined by the insulating interlayer and the metal electrode,forming a second electrode passivation film along a profile defined bythe first electrode passivation film, patterning the second electrodepassivation film to form a second electrode passivation film patternexposing a portion of the first electrode passivation film correspondingto the metal electrode, and patterning the first electrode passivationfilm using the second electrode passivation film pattern as an etch maskto form a first electrode passivation film pattern exposing the uppersurface of the metal electrodes.

Here, the first electrode passivation film may be formed using amaterial of one of oxide or nitride, and the second electrodepassivation film is formed using a material of the other of oxide ornitride.

According to an example embodiment of the present invention, an OLEDdisplay device may include a signal control unit including a substratestructure including a plurality of active elements for pixels, a lowermetal pattern disposed on the substrate structure, and being configuredto be electrically connected to a portion of at least one of the activeelements, an insulating interlayer disposed on the substrate structureto cover the lower metal pattern, a via contact penetrating through theinsulating interlayer to be connected to the lower metal pattern, ametal electrode disposed on the insulating interlayer, and beingconfigured to be connected to the via contact and an electrodepassivation layer pattern covering a peripheral portion of an uppersurface and the side surface of the metal electrode to expose a centerportion of the upper surface of the metal electrode such that leakagecurrent which flows through the side surface of the metal electrode issuppressed, an organic light emitting unit disposed over the signalcontrol unit, the organic light emitting unit including a plurality oflight emitting regions for each of pixels, and a protection unitentirely covering the organic light emitting unit, the protection unitincluding a color filter layer.

According to example embodiments of the present invention, the signalcontrol unit includes the electrode passivation layer pattern coveringthe upper faces and side surfaces of the metal electrodes, which isformed through a dry etching process instead of a planarization process.Therefore, the upper surfaces of the metal electrodes may be suppressedfrom being damaged. In addition, since the electrode passivation layerpattern covers the side surfaces of the metal electrodes, leakage ofcurrent through the side surfaces of the metal electrodes can beprevented.

Since the via contacts of the signal control unit according to exampleembodiment of the present invention are connected to the peripheralportions of the lower surfaces of the metal electrodes, the stepportions of the metal electrodes, which are generated due to the dishingof the via contacts, may be formed at the peripheral portions of themetal electrodes. Therefore, an effect of the step portions of the metalelectrodes may be minimized.

In addition, the electrode passivation layer pattern may cover the stepportions formed on the peripheral portions of the upper surfaces of themetal electrodes. Therefore, a decrease in reflectivity of the metalelectrodes can be prevented.

Therefore, deterioration in optical characteristics of the organic lightemitting diode display device including the signal control unit may beprevented.

The above summary is not intended to describe each illustratedembodiment or every implementation of the subject matter hereof. Thefigures and the detailed description that follow more particularlyexemplify various embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

Example embodiments can be understood in more detail from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a cross sectional view illustrating a signal control unit foran OLED display device in accordance with an example embodiment of thepresent invention;

FIG. 2 is a plan view illustrating a positional relation between viacontacts, metal electrodes and an electrode passivation layer pattern;

FIG. 3 is a cross sectional view illustrating a signal control unit foran OLED device in accordance with an example embodiment of the presentinvention;

FIGS. 4 to 6 are cross sectional views illustrating a method ofmanufacturing a signal control unit of an OLED display device inaccordance with an example embodiment of the present invention;

FIGS. 7 and 8 are cross sectional views illustrating a method ofmanufacturing a signal control unit of an OLED display device inaccordance with an example embodiment of the present invention;

FIG. 9 is a block diagram illustrating an OLED display device inaccordance with an example embodiment of the present invention; and

FIG. 10 is a cross sectional view illustrating the OLED display deviceshown in FIG. 9.

While various embodiments are amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It should beunderstood, however, that the intention is not to limit the claimedinventions to the particular embodiments described. On the contrary, theintention is to cover all modifications, equivalents, and alternativesfalling within the spirit and scope of the subject matter as defined bythe claims.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, specific embodiments will be described in more detail withreference to the accompanying drawings. The present invention may,however, be embodied in different forms and should not be construed aslimited to the embodiments set forth herein.

As an explicit definition used in this application, when a layer, afilm, a region or a plate is referred to as being ‘on’ another one, itcan be directly on the other one, or one or more intervening layers,films, regions or plates may also be present. Unlike this, it will alsobe understood that when a layer, a film, a region or a plate is referredto as being ‘directly on’ another one, it is directly on the other one,and one or more intervening layers, films, regions or plates do notexist. Also, though terms like a first, a second, and a third are usedto describe various components, compositions, regions and layers invarious embodiments of the present invention are not limited to theseterms.

Furthermore, and solely for convenience of description, elements may bereferred to as “above” or “below” one another. It will be understoodthat such description refers to the orientation shown in the Figurebeing described, and that in various uses and alternative embodimentsthese elements could be rotated or transposed in alternativearrangements and configurations.

In the following description, the technical terms are used only forexplaining specific embodiments while not limiting the scope of thepresent invention. Unless otherwise defined herein, all the terms usedherein, which include technical or scientific terms, may have the samemeaning that is generally understood by those skilled in the art.

The depicted embodiments are described with reference to schematicdiagrams of some embodiments of the present invention. Accordingly,changes in the shapes of the diagrams, for example, changes inmanufacturing techniques and/or allowable errors, are sufficientlyexpected. Accordingly, embodiments of the present invention are notdescribed as being limited to specific shapes of areas described withdiagrams and include deviations in the shapes and also the areasdescribed with drawings are entirely schematic and their shapes do notrepresent accurate shapes and also do not limit the scope of the presentinvention.

FIG. 1 is a cross sectional view illustrating a signal control unit foran OLED display device in accordance with an example embodiment. FIG. 2is a plan view illustrating a positional relationship between viacontacts, metal electrodes and an electrode passivation layer pattern.

Referring to FIGS. 1 and 2, a signal control unit 100 for an OLEDdisplay device in accordance with an example embodiment of the presentinvention includes a substrate structure 110, lower metal patterns 120,an insulating interlayer 130, via contacts 140, metal electrodes 150 andan electrode passivation layer pattern 160.

The signal control unit 100 may control signals for driving each of aplurality of pixels included in an OLED display device. Further, thesignal control unit 100 may control a path of light which is generatedby a light emitting unit (not shown) positioned over the signal controlunit 100.

The substrate structure 110 may control electric signals to be appliedto each of the pixels of the light emitting unit. That is, the substratestructure 110 may includes a substrate (not shown) and active elements(not shown) corresponding to each of pixels.

The substrate, for example, includes a glass substrate or a polyimidesubstrate having a flexible characteristic.

The active elements include, for example, a plurality of diodes ortransistors. Further, each of the active elements may include anerasable programmable read only memory (EPROM) capable of erasing databy irradiating ultraviolet light, and an electrically erasableprogrammable read only memory (EEPROM) capable of erasing data usingelectricity instead of ultraviolet light. Each of the active elementsmay control a signal using a floating gate where electrical charges arecharged or erased so that the data can be removed.

The active elements may control the light emitting unit by applying anelectrical signal to the light emitting unit via the lower metalpatterns 120, the via contacts 140, and the metal electrodes 150.

The lower metal patterns 120 are disposed on the substrate structure110. Each of the lower metal patterns 120 may be connected to one of theactive elements. When the active elements include transistors, each ofthe lower metal patterns 120 may be connected to a source or drainterminal of a corresponding transistor.

The lower metal patterns 120 may be made of copper, aluminum, tungsten,or an alloy thereof, for example.

The insulating interlayer 130 is disposed on the substrate structure 110to cover the lower metal patterns 120. The insulating interlayer 130 mayinclude oxide or nitride. Further, the insulating interlayer 130 mayhave a stack structure including an oxide layer and a nitride layerwhich are sequentially stacked on the substrate structure 110.

The via contacts 140 penetrates through the insulating interlayer 130 tobe connected to upper surfaces of the lower metal patterns 120. Each ofthe via contacts 140 extends in a vertical direction. The via contacts140 may include copper, aluminum, tungsten, or an alloy thereof, forexample.

The via contacts 140 are provided in the insulating interlayer 130.Therefore, the via contacts 140 may electrically connect the lower metalpatterns 120 and the metal electrodes 150 with one another.

The metal electrodes 150 are disposed on the insulating interlayer 130.Each of the metal electrodes 150 is connected to each of the viacontacts 140. Each of the metal electrodes 150 corresponds to each ofthe lower metal patterns 120. Each of the lower metal patterns 120 andthe metal electrodes 150 may be electrically connected to each otherthrough each of the via contacts 140.

When the active elements include transistor, each of the lower metalpatterns 120 is connected to a source/drain terminal of the transistorso that each of the metal electrodes 150 may function as an anodeelectrode.

The metal electrodes 150 may be formed of metal material identical tothat of the lower metal patterns 120. That is, the metal electrodes 150may be made of copper, aluminum, tungsten, or an alloy thereof, forexample.

While forming the via contacts 140, dishing phenomena in which the uppersurfaces of the via contacts 140 are concave in the process ofplanarizing the upper surfaces of the via contacts 140 may occur. A stepportion may be formed in the metal electrodes 150 due to dishing of thevia contacts 140.

The via contacts 140 may be provided in at least one capable ofconnecting one of the lower electrodes 120 with one of the correspondingmetal electrodes 150. In this case, each of the via contacts 140 mayconnect a peripheral portion of an upper surface of each of the lowermetals 120 with a peripheral portion of a lower surface of each of themetal electrode 150, respectively.

While performing a process for forming the via contacts 140, aplanarization process may be required to planarize the upper surfaces ofthe via contacts, which may cause dishing phenomena to occur to make theupper surfaces of the via contacts to be concave. Therefore, the metalelectrodes 150 disposed on the via contacts may include a step portionthereon.

Since the via contacts 140 are connected to the peripheral portions ofthe lower surfaces of the metal electrodes 150, the step portions of themetal electrodes 150, which may be generated due to the dishingphenomena which occur to the via contacts 140, may be formed at aperipheral portion thereof, instead at a central portion thereof.Therefore, an influence of the step portions of the metal electrodes 150may be decreased.

The electrode passivation layer pattern 160 is disposed on the metalelectrodes 150 and the insulating interlayer 130 to expose centerportions of the upper surfaces of the metal electrodes 150. Therefore,the electrode passivation layer pattern 160 covers peripheral portionsand side surfaces of the metal electrodes 150.

The electrode passivation layer pattern 160 may include the materialidentical as that of the insulating interlayer 130. Alternatively, theelectrode passivaiton layer pattern 160 may be formed of a materialdifferent from that of the insulating interlayer 130. For example, theelectrode passivation film pattern 160 may include oxide or nitride

The electrode passivation layer pattern 160 may be formed by a dryetching process, rather than a planarization process, in embodiments.Therefore, since the planarization process is not performed, the uppersurface of the metal electrodes 150 can be prevented from being damaged,dished, or stepped in shape.

In addition, since the electrode passivation layer pattern 160 coversthe side surfaces of the metal electrodes 150, leakage of currentthrough the side surfaces of the metal electrodes 150 may be suppressed.

The electrode passivation layer pattern 160 may cover the step portionsformed on the peripheral portions of the upper surface of the metalelectrodes 150. Therefore, the reflectivity of the metal electrodes 150may be suppressed from being lowered due to the step portions. Inaddition, deterioration in optical characteristics of the OLED displaydevice including the signal control unit 100 may be prevented.

FIG. 3 is a cross sectional view illustrating a signal control unit foran OLED device in accordance with an embodiment of the presentinvention.

Referring to FIG. 3, a signal control unit 200 for an OLED displayincludes a substrate structure 210, lower metal layers 220, aninsulating interlayer 230, via contacts 240, metal electrodes 250, andan electrode passivation layer pattern 260. Since the substratestructure 210, the lower metal layers 220, the insulating interlayer230, the via contacts 240, and the metal electrodes 250 aresubstantially identical to their counterparts (substrate structure 110,lower metal layers 120, the insulating interlayer 130, the via contacts140, and the metal electrodes 150) described with respect to FIGS. 1 and2, detailed description will be omitted in order to avoid anyredundancy.

The electrode passivation layer pattern 260 includes a first passivationfilm pattern 262 and a second passivation film pattern 264.

The first passivation film pattern 262 is disposed on the metalelectrodes 250 and the insulating interlayer 230 while exposing a centerportion of the top surface of the metal electrodes 250. Accordingly, thefirst passivation film pattern 262 covers peripheral portions and sidesurfaces of the metal electrodes 250.

The second passivation film pattern 264 is disposed on the firstpassivation film pattern 262. The second passivation film pattern 264may be used as an etch mask pattern in an etch process for forming thefirst passivation film pattern 262.

Although not shown, the first passivation film pattern 262 and thesecond passivation film pattern 264 may be formed to entirely expose thetop surfaces of the metal electrodes 250.

The first passivation film pattern 262 may be formed of materialsdifferent from that of the second passivation film pattern 264. Forexample, the first passivation film pattern 262 may be formed of one ofoxide and nitride, and the second passivation film pattern 264 may bethe other.

The electrode passivation layer pattern 260 may be formed by a dryetching process, rather than a planarization process. Therefore, sincethe planarization process is not performed, the upper surfaces of themetal electrodes 150 may be prevented from being damaged.

Also, since the first passivation film pattern 262 covers the sidesurfaces of the metal electrodes 250, leakage current which flowsthrough the side surfaces of the metal electrodes 250 may be prevented.

The first passivation film pattern 262 and the second passivation filmpattern 264 may continuously cover the step portions which arepositioned at peripheral portions of upper surfaces of the metalelectrodes 250. Therefore, a decrease of the reflectivity of the metalelectrodes 250, which occurs due to the step portions, may be prevented.In addition, deterioration in optical characteristics of the OLEDdisplay device including the signal control unit 200 may be prevented.

FIGS. 4 to 6 are cross sectional views illustrating a method ofmanufacturing a signal control unit of an OLED display device inaccordance with an example embodiment of the present invention.

Referring to FIG. 4, according to an example embodiment of a method ofmanufacturing a signal control unit for an OLED display device, asubstrate structure 110 including active elements for each pixel isprepared.

The substrate structure 110 may be prepared by forming active elements(not shown) formed on the substrate for each pixel.

The active elements are formed to include, for example, a diode or atransistor. Further, the active elements may include an erasableprogrammable read only memory (EPROM) capable of erasing data byirradiating ultraviolet light, or an electrically erasable programmableread only memory (EEPROM) capable of erasing data using electricityinstead of ultraviolet light. The active elements may control a signalusing a floating gate. Electric charges are charged or erased in thefloating gate, so that data may be removed.

Subsequently, lower metal patterns 120 are formed on the substratestructure 110 to be electrically connected to the active elementspartially.

In order to form the lower metal patterns 120, a first metal layer (notshown) is firstly formed on the substrate structure 110. The first metallayer may be formed through a sputtering process or a chemical vapordeposition process. Then, the first metal layer is patterned totransform the first metal layer into the lower metal patterns 120. Inorder to pattern the first metal layer, an etching process may beperformed.

An insulating interlayer 130 is formed on the substrate structure 110 tocover the lower metal patterns 120. The insulating interlayer 130 may beformed through a plasma enhanced chemical vapor deposition process. Theinsulating interlayer 130 may be formed using oxide or nitride. Theinsulating interlayer 130 may be formed in a single layer or a multiplelayers.

Referring to FIG. 5, via contacts 140 are formed to penetrate throughthe insulating interlayer 130. Therefore, the via contacts 140 extend ina vertical direction to be connected with the lower metal patterns 120.The insulating interlayer 130 is partially etched to form via holes toexpose an upper surface of each of the lower metal patterns 120. Then,the via holes are filled with a metal material to form via contacts 140.

Next, metal electrodes 150 are formed on the insulating interlayer 130to be electrically connected to the lower metal patterns 120 through thevia contacts 140. The metal electrodes 150 may be made of metal materialthe same as that of the lower metals 120. That is, the metal electrodes150 may be made of copper, aluminum, tungsten, or an alloy thereof.

In order to form the metal electrodes 150, a second metal layer (notshown) is formed on the insulating interlayer 130. The second metallayer may be formed through a sputtering process or a chemical vapordeposition process. Then, the second metal layer is patterned totransform the second metal layer into the metal electrodes 150. In orderto pattern the second metal layer, an etching process may be performed.

Each of the metal electrodes 150 may be formed to correspond to each ofthe lower metal patterns 120. Each of the metal electrodes 150 may beelectrically connected to each of the lower metal patterns 120 throughthe via contacts 140.

Meanwhile, the via contacts 140 may be provided in at least one capableof connecting one of the lower electrodes 120 with one of thecorresponding metal electrodes 150. In this case, each of the viacontacts 140 may connect a peripheral portion of an upper surface ofeach of the lower metal 120 with a peripheral portion of a lower surfaceof each of the metal electrode 150, respectively.

While performing a process for forming the via contacts 140, aplanarization process may be required to planarize the upper surfaces ofthe via contacts, which may cause dishing phenomena to occur to make theupper surfaces of the via contacts to be concave. Therefore, one of themetal electrodes 150 disposed on the via contacts may have a stepportion.

Since the via contacts 140 are connected to the peripheral portions ofthe lower surfaces of the metal electrodes 150, the step portions of themetal electrodes 150, which may occur due to the dishing phenomena whichoccurs to the via contacts 140, may be formed at a peripheral portionthereof, not at a central portion thereof. Therefore, an influence ofthe step portions of the metal electrodes 150 may be decreased.

Referring to FIG. 6, an electrode passivation layer pattern 160 isformed on the metal electrodes 150 and the insulating interlayer 130 toexpose center portions of the upper surfaces of the metal electrodes150.

In order to form the electrode passivation layer pattern 160, anelectrode passivaiton layer (not shown) is formed on the insulatinginterlayer 130 so as to cover the metal electrodes 150. The electrodepassivation layer may be formed through a plasma enhanced chemical vapordeposition process.

The electrode passivation layer may be formed using a material identicalas that of the insulating interlayer 130. Alternatively, the electrodepassivation layer may be formed of a material different from that of theinsulating interlayer 130. For example, the electrode passivation layercan include oxide or nitride

Then, the electrode passivation layer is patterned to form the electrodepassivation layer pattern 160. In order to pattern the electrodepassivation layer, a dry etching process may be performed.

The electrode passivation layer pattern 160 exposes the center portionsof the upper surfaces of the metal electrodes 150 and covers theperipheral portions and side surfaces of the metal electrodes 150.

Meanwhile, although not shown, the electrode passivation layer pattern160 may entirely expose the upper surface of the metal electrodes 150.

The electrode passivation layer pattern 160 may be formed by a dryetching process, not a planarization process. Therefore, since theplanarization process is not performed, the upper surface of the metalelectrodes 150 can be prevented from being damaged.

In addition, since the electrode passivation layer pattern 160 coversthe side surfaces of the metal electrodes 150, leakage of currentthrough the side surfaces of the metal electrodes 150 may be suppressed.

The electrode passivation layer pattern 160 may cover the step portionsformed on the peripheral portions of the upper surface of the metalelectrodes 150. Therefore, the reflectivity of the metal electrodes 150may be suppressed from being lowered due to the step portions. Inaddition, deterioration in optical characteristics of the organic lightemitting diode (OLED) display device including the signal control unit100 may be prevented.

FIGS. 7 and 8 are cross sectional views illustrating a method ofmanufacturing a signal control unit of an OLED display device inaccordance with an example embodiment of the present invention.

Referring to FIG. 7, since the processes for forming a substratestructure 210, lower metal patterns 220, an insulating interlayer 230,the via contacts 240, and the metal electrodes 250 are substantiallyidentical to those for forming the lower metal layers 120, theinsulating interlayer 130, the via contacts 140, and the metalelectrodes 150 illustrated with respect to FIGS. 4 and 6, detaileddescription will be omitted in order to avoid any redundancy.

An electrode passivation layer pattern 260 (see FIG. 8) is formed on themetal electrodes 250 and the insulating interlayer 230 to expose thecenter portions of the upper surfaces of the metal electrodes 250.

A first passivation film 261 and a second passivation film 263 aresequentially formed on the insulating interlayer 230 to cover the metalelectrodes 250 in order to form the electrode passivation layer pattern260. The first passivation film 261 and the second passivation film 263may be formed through a plasma enhanced chemical vapor depositionprocess.

The first passivation film 261 and the second passivation film 263 maybe formed of different materials. For example, the first passivationfilm 261 may be formed of one of oxide and nitride, and the secondpassivation film 263 may be formed of the other.

Referring to FIG. 8, the first passivation film 261 and the secondpassivation film 263 are dry-etched to form the electrode passivationlayer pattern 260 including the first passivation film pattern 262 andthe second passivation film pattern 264.

Specifically, the second passivation film 263 is patterned to form thesecond passivation film pattern 264 having portions of the secondpassivation film pattern 264 corresponding to the center portions of theupper surfaces of the metal electrodes 250 open. In order to pattern thesecond passivation film 263, a dry etching process may be performed.

Next, the first passivation film 261 is patterned to form the firstpassivation film pattern 262. The first passivation film 261 ispatterned through a dry etching process using the second passivationfilm pattern 264 as an etching mask.

The first passivation film pattern 262 covers the peripheral portion ofthe upper surfaces and the side surfaces of the metal electrodes 250,while exposing the center portions of the upper surfaces of the metalelectrodes 250.

Although not shown, the first passivation film pattern 262 and thesecond passivation film pattern 264 may be formed to entirely expose theupper surfaces of the metal electrodes 250.

Since the electrode passivation layer pattern 260 is formed by a dryetching process instead of a planarization process, the upper surfacesof the metal electrodes 250 may be suppressed from being damaged.

Also, since the first passivation film pattern 262 covers the sidesurfaces of the metal electrodes 250, leakage of current which may flowsthrough the side surfaces of the metal electrodes 250 may be prevented.

The first passivation film pattern 262 and the second passivation filmpattern 264 may continuously cover the step portions formed on theperipheral portions of the upper surfaces of the metal electrodes 250.Therefore, a decrease of the reflectivity of the metal electrodes 250,which may occur due to the step portions, may be prevented. In addition,deterioration in optical characteristics of the organic light emittingdiode display device of the signal control unit 200 may be prevented.

FIG. 9 is a block diagram illustrating an OLED display device inaccordance with an example embodiment of the present invention. FIG. 10is a cross sectional view illustrating the OLED device shown in FIG. 9.

Referring to FIGS. 9 and 10, an OLED device 300 according to an exampleembodiment of the present invention includes a signal control unit 310,an organic light emitting unit 330, and a protection unit 350.

Since the signal control unit 310 has been described above withreference to FIGS. 1 and 2, a detailed description on the signal controlunit 310 will be omitted.

The organic light emitting unit 330 is provided on the signal controlunit 310. The organic light emitting unit 330 is driven by a signalgenerated from the signal control unit 310.

The organic light emitting unit 330 includes an anode electrode 331, ahole transport layer 332, a light emitting layer 335, an electrontransport layer 338 and a cathode electrode 339.

Holes injected into the anode electrode 331 move to an emission layer335 through a hole transfer layer 332. Electrons injected from thecathode 339 are transferred to the light emitting layer 335 through anelectron transfer layer 338. The holes/electrons collected to the lightemitting layer 335 are recombined to emit light.

One portion of the light emitted as described above is emitted to theoutside through a color filter layer included in the passivation unit350, thereby realizing an image. Meanwhile, another portion of the lightis directed to the substrate structure 310 and is irradiated downward.

Since the electrode passivation layer pattern covers the step portionsformed on the peripheral portions of the upper surfaces of the metalelectrodes to prevent the reflectivity of the metal electrodes fromlowering, and the light may be stably reflected from the metalelectrodes. Therefore, the optical characteristics of the OLED displaydevice may be improved.

In addition, since the electrode passivation layer pattern covers theside surfaces of the metal electrodes, leakage of current which flowsthrough the side surfaces of the metal electrodes may be prevented.Therefore, the reliability of the OLED display device may be enhanced.

As described above, the signal control unit according to exampleembodiments of the present invention may prevent current from leakingthrough the side surfaces of the metal electrodes, may minimize theinfluence due to the step portions of the metal electrode so as toreduce the reflectivity of the metal electrodes. Therefore,deterioration in optical characteristics of the OLED display deviceincluding the signal control unit may be prevented.

Although the signal control unit and the OLED device have been describedwith reference to the specific embodiments, they are not limitedthereto. Therefore, it will be readily understood by those skilled inthe art that various modifications and changes can be made theretowithout departing from the spirit and scope of the appended claims.

Various embodiments of systems, devices, and methods have been describedherein. These embodiments are given only by way of example and are notintended to limit the scope of the claimed inventions. It should beappreciated, moreover, that the various features of the embodiments thathave been described may be combined in various ways to produce numerousadditional embodiments. Moreover, while various materials, dimensions,shapes, configurations and locations, etc. have been described for usewith disclosed embodiments, others besides those disclosed may beutilized without exceeding the scope of the claimed inventions.

Persons of ordinary skill in the relevant arts will recognize that thesubject matter hereof may comprise fewer features than illustrated inany individual embodiment described above. The embodiments describedherein are not meant to be an exhaustive presentation of the ways inwhich the various features of the subject matter hereof may be combined.Accordingly, the embodiments are not mutually exclusive combinations offeatures; rather, the various embodiments can comprise a combination ofdifferent individual features selected from different individualembodiments, as understood by persons of ordinary skill in the art.Moreover, elements described with respect to one embodiment can beimplemented in other embodiments even when not described in suchembodiments unless otherwise noted.

Although a dependent claim may refer in the claims to a specificcombination with one or more other claims, other embodiments can alsoinclude a combination of the dependent claim with the subject matter ofeach other dependent claim or a combination of one or more features withother dependent or independent claims. Such combinations are proposedherein unless it is stated that a specific combination is not intended.

Any incorporation by reference of documents above is limited such thatno subject matter is incorporated that is contrary to the explicitdisclosure herein. Any incorporation by reference of documents above isfurther limited such that no claims included in the documents areincorporated by reference herein. Any incorporation by reference ofdocuments above is yet further limited such that any definitionsprovided in the documents are not incorporated by reference hereinunless expressly included herein.

For purposes of interpreting the claims, it is expressly intended thatthe provisions of 35 U.S.C. § 112(f) are not to be invoked unless thespecific terms “means for” or “step for” are recited in a claim.

We claim:
 1. A signal control unit for an organic light emitting diode(OLED) display device comprising: a substrate structure including aplurality of active elements each corresponding to a pixel; a lowermetal pattern disposed on the substrate structure, and electricallyconnected to a portion of the plurality of active elements; aninsulating interlayer disposed on the substrate structure and at leastpartially covering the lower metal pattern; a via contact penetratingthrough the insulating interlayer and connected to the lower metalpattern; a metal electrode disposed on the insulating interlayer, andconnected to the via contact; and an electrode passivation layer patternsubstantially covering the metal electrode to expose a center portion ofan upper surface of the metal electrode while covering a remainder ofthe upper surface and a side surface of the metal electrode.
 2. Thesignal control unit of claim 1, wherein the electrode passivation layerpattern comprises: a first passivation film pattern arranged on theremainder of the upper surface and the side surface of the metalelectrode; and a second passivation film pattern disposed on the firstpassivation film pattern.
 3. The signal control unit of claim 1, whereinthe via contact is connected to a peripheral portion of a lower surfaceof the metal electrode such that the metal electrode includes a stepportion at the peripheral portion thereof corresponding to a dishingphenomena caused by formation of the via contacts.
 4. The signal controlunit of claim 3, wherein the electrode passivation layer pattern coversthe step portion to suppress the peripheral portion of the metalelectrodes from being exposed.
 5. A method of manufacturing a signalcontrol unit for an organic light emitting diode (OLED) display device,the method comprising: preparing a substrate structure including aplurality of active elements each corresponding to a pixel; forming alower metal pattern on the substrate structure, the lower metal patternbeing adapted to be electrically connected to at least one of theplurality of active elements; forming an insulating interlayer on thesubstrate structure to cover the lower metal pattern; forming a viacontact penetrating through the insulating interlayer, the via contactbeing connected to the lower metal pattern; and forming a metalelectrode on the insulating interlayer and connected to the via contact;forming an electrode passivation layer pattern covering a peripheralportion of an upper surface and a side surface of the metal electrodesto expose a center portion of the upper surface of the metal electrodesuch that leakage current which flows through the side surface of themetal electrodes is suppressed.
 6. The method of claim 5, wherein thevia contact is connected to a peripheral portion of a lower surface ofthe metal electrode such that the metal electrode includes a stepportion at the peripheral portions thereof, which may occur due todishing phenomena caused by the via contacts.
 7. The method of claim 6,wherein the electrode passivation layer pattern is formed to cover thestep portion to suppress the peripheral portions of the metal electrodesfrom being exposed.
 8. The method of claim 5, wherein forming theelectrode passivation layer pattern comprises: forming an electrodepassivation layer along a profile defined by the insulating interlayerand the metal electrode; and performing a dry etch process against theelectrode passivaiton layer using an etch selectivity between theelectrode passivation layer and the metal electrode to pattern theelectrode passivation layer.
 9. The method of claim 8, wherein theelectrode passivation layer is formed using a material of one of oxideor nitride.
 10. The method of claim 5, wherein forming the electrodepassivation layer pattern comprises: forming a first electrodepassivation film along a profile defined by the insulating interlayerand the metal electrode; forming a second electrode passivation filmalong a profile defined by the first electrode passivation film;patterning the second electrode passivation film to form a secondelectrode passivation film pattern by exposing a portion of the firstelectrode passivation film corresponding to the metal electrode; andpatterning the first electrode passivation film using the secondelectrode passivation film pattern as an etch mask to form a firstelectrode passivation film pattern and exposing the upper surface of themetal electrodes.
 11. The method of claim 10, wherein the firstelectrode passivation film is formed using a material selected from agroup consisting of oxide and nitride, and the second electrodepassivation film is formed using the other of the group consisting ofoxide and nitride.
 12. An organic light emitting diode (OLED) displaydevice, comprising: a signal control unit including a substratestructure including a plurality of active elements for pixels, a lowermetal pattern disposed on the substrate structure, and electricallyconnected to a portion of at least one of the plurality of activeelements, an insulating interlayer disposed on the substrate structureto cover the lower metal pattern, a via contact penetrating through theinsulating interlayer to be connected to the lower metal pattern, ametal electrode disposed on the insulating interlayer, and connected tothe via contact and an electrode passivation layer pattern covering aperipheral portion of an upper surface and the side surface of the metalelectrode to expose a center portion of the upper surface of the metalelectrode such that leakage current which flows through the side surfaceof the metal electrode is suppressed; an organic light emitting unitdisposed over the signal control unit, the organic light emitting unitincluding a plurality of light emitting regions for each of pixels; anda protection unit entirely covering the organic light emitting unit, theprotection unit including a color filter layer.
 13. The OLED displaydevice of claim 12, wherein the electrode passivation layer patterncomprises: a first passivation film pattern arranged on the remainder ofthe upper surface and the side surface of the metal electrode; and asecond passivation film pattern disposed on the first passivation filmpattern.
 14. The OLED display device of claim 12, wherein the viacontact is connected to a peripheral portion of a lower surface of themetal electrode such that the metal electrode includes a step portion atthe peripheral portion thereof corresponding to a dishing phenomenacaused by formation of the via contacts.
 15. The OLED display device ofclaim 14, wherein the electrode passivation layer pattern covers thestep portion to suppress the peripheral portion of the metal electrodesfrom being exposed.